SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0cfc3bc230fcc6a8c037f0e1a5b378a0e1573927978d7a338b6ea361328c3216' 
  AND token = 'gzNxTlOGtUo5FvcTEawixaBBFSYk+WYWdW2ME1fWQ1g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00016

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}